The Carian language is an extinct language of the Luwian subgroup of the Anatolian branch of the Indo-Europeanlanguage family. The Carian language was spoken in Caria, a region of western Anatolia between the ancient regions of Lycia and Lydia, by the Carians, a name possibly first mentioned in Hittite sources. Prior to the late 20th century CE the language remained a total mystery even though many characters of the script appeared to be from the Greek alphabet. Using Greek phonetic values of letters investigators of the 19th and 20th centuries were unable to make headway and classified the language as non-Indo-European. Speculations multiplied, none very substantial. Progress finally came as a result of rejecting the presumption of Greek phonetic values.

Carian is closely related to Lycian and Milyan (Lycian B), and both are closely related to, though not direct descendants of, Luwian. Whether the correspondences between Luwian, Carian, and Lycian are due to direct descent (i.e. a language family as represented by a tree-model), or are due to dialect geography, is disputed.[7]

The Achaean Greeks arriving in small numbers on the coasts of Anatolia in the Late Bronze Age found them occupied by a population that did not speak Greek and were generally involved in political relationships with the Hittite Empire. After the fall of the latter the region became the target of heavy immigration by Ionian and Dorian Greeks who enhanced Greek settlements and founded or refounded major cities. They assumed for purposes of collaboration new regional names based on their previous locations: Ionia, Doris.

The writers born in these new cities reported that the people among whom they had settled were called Carians and spoke a language that was "barbarian", "barbaric" or "barbarian-sounding." No clue has survived from these writings as to what exactly the Greeks might mean by "barbarian." The reportedly Carian names of the Carian cities did not and do not appear to be Greek. Such names as Andanus, Myndus, Bybassia, Larymna, Chysaoris, Alabanda, Plarasa and Iassus were puzzling to the Greeks, some of whom attempted to give etymologies in words they said were Carian. For the most part they still remain a mystery.

Writing disappeared in the Greek Dark Ages but no earlier Carian writing has survived. When inscriptions, some bilingual, began to appear in the 7th century BCE it was already some hundreds of years after the city-naming phase. The earlier Carian may not have been exactly the same.

The local development of Carian excludes some other theories as well: it was not widespread in the Aegean, is not related to Etruscan, was not written in any ancient Aegean scripts, and was not a substrate Aegean language. Its occurrence in various places of Classical Greece is due only to the travel habits of Carians, who apparently became co-travellers of the Ionians. The Carian cemetery of Delos probably represents the pirates mentioned in classical texts. The Carians who fought for Troy if they did were not classical Carians any more than the Greeks there were classical Greeks.

Being penetrated by larger numbers of Greeks and under the domination from time to time of the Ionian League, Caria eventually Hellenized and Carian became a dead language. The interludes under the Persian Empire perhaps served only to delay the process. Hellenization would lead to the extinction of the Carian language in the 1st century BCE or early in the Common Era.